CENTRAL GROUND WATER BOARD
State Profile
Ground Water Scenario of Andhra Pradesh
Area (Sq. km) |
159918 |
Physiography |
A low relief terrain with three major physiographic units-
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Drainage |
The State is drained by three major perennial rivers viz. Godavari, Krishna and Pennar, ten medium rivers and several other rivers of lesser significance |
Irrigation |
Gross Area irrigated is 41,54,322 Ha, out of which area irrigated by ground water is 15,61,170 Ha(37.6%) and the area irrigated by surface water is 24,49,665 Ha ( 59%). |
Rainfall |
Varies from 574 mm in Anantapur district to 1166 mm in Srikakulam district. It increases from less than 800 mm in the south and south-west part of the state to more than 1200 mm in north and north-east part of the state. The mean annual rainfall of the state is 950 mm of which southwest monsoon season ( June-September) contributes about 58% of the annual rainfall and northeast monsoon season contributes 305 mm of the annual rainfall. |
Total Districts / Mandals |
13 Districts / 664 Mandals |
Hydrogeology
Andhra Pradesh is characterized by various geological formations ranging in age from Archaean to Recent. Nearly 67percent of the State is underlain by hard rock formations consisting of granites, gneisses, metamorphics and intrusives (Archaeans), Precambrian quartzites, shales and limestones (Cuddapahs & Kurnools), Mesozoic Deccan Trap basalts etc., while the remaining area is underlain by Gondwana, Tertiary sedimentaries and Sub Recent-Recent alluvium. The occurrence and movement of ground water in hard rocks is chiefly controlled by thickness of weathering and structural features like fractures and solution cavities. In general, the depth of weathering varies from 5 to 20 m and occasionally upto 40 m. Ground water is developed generally by means of shallow-deep bore wells ranging in depth down to 100 m, occasionally even beyond 100 m with discharges generally ranging from 2-5 lps. The semi-consolidated formations of Gondwana & Tertiary comprising sandstones, shales, siltstones, conglomerates form thick and multi aquifer systems down to 600 m bgl under confining conditions. The aquifers are often prolific with discharges varying upto as high as 100 lps. Ground water in coastal alluvium, deltaic alluvium representing un-consolidated formations is generally saline with fresh water restricting to shallow depths (< 20 m).
Dynamic Ground Water Resources (2011) |
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Annual Replenishable Ground water Resource |
20.78 BCM |
Net Annual Ground Water Availability |
18.88 BCM |
Annual Ground Water Draft |
7.01 BCM |
Stage of Ground Water Development |
37 % |
Ground Water Development & Management |
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Over Exploited |
41 Mandals |
Critical |
7 Mandals |
Semi- critical |
42 Mandals |
Artificial Recharge to Ground Water |
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Ground Water Quality Problems |
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Contaminants |
Districts affected (in part) |
Salinity (EC > 3000 µS/cm at 25 ° C) |
Ananthapur, East-Godavari, Guntur, Kadapa, Krishna, Kurnool, Nellore, Prakasam, Srikakulam, Visakhapatnam, West-Godavari |
Fluoride (>1.5 mg/l) |
Anantpur, Chittoor, Guntur, Kadapa, Krishna, Kurnool, Nellore, Prakasam, Visakhapatnam, Vizianagaram, West Godavari |
Iron (>1.0 mg/l) |
Chittoor, Cuddapah, Guntur, Krishna, Kurnool, Nellore, Vishakhapatnam |
Nitrate (>45 mg/l) |
All the districts of the state |
Central Ground Water Authority
Areas Notified for Regulation of ground water development |
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